CN104010263B - Method and detector for diaphragm of loudspeaker offset - Google Patents
Method and detector for diaphragm of loudspeaker offset Download PDFInfo
- Publication number
- CN104010263B CN104010263B CN201410065381.1A CN201410065381A CN104010263B CN 104010263 B CN104010263 B CN 104010263B CN 201410065381 A CN201410065381 A CN 201410065381A CN 104010263 B CN104010263 B CN 104010263B
- Authority
- CN
- China
- Prior art keywords
- signal
- loudspeaker
- probe signal
- audio
- digital
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R29/00—Monitoring arrangements; Testing arrangements
- H04R29/001—Monitoring arrangements; Testing arrangements for loudspeakers
- H04R29/003—Monitoring arrangements; Testing arrangements for loudspeakers of the moving-coil type
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R3/00—Circuits for transducers, loudspeakers or microphones
- H04R3/007—Protection circuits for transducers
Abstract
The present invention is related to the method for detecting the vibrating diaphragm offset of dynamic loudspeaker in one aspect.This method includes the steps that generating the audio signal of the voice coil applied to dynamic loudspeaker and high frequency probe signal being increased to the audio signal to generate composite drive signal.This method further includes the steps that the composite drive signal is applied to the voice coil by output amplifier and detects the modulation level for the probe signal electric current for flowing through the voice coil.
Description
Technical field
The present invention is related to the method for detecting the vibrating diaphragm offset of dynamic loudspeaker in one aspect.This method includes generating application
In the voice coil of dynamic loudspeaker audio signal and high frequency probe signal is increased into the audio signal to generate combination flooding
The step of dynamic signal.This method further includes that the composite drive signal is applied to the voice coil by output amplifier and is examined
The step of modulation level of the probe signal electric current of the excessively described voice coil of flow measurement.
Background technology
The present invention relates to the methods and the inspection of corresponding loudspeaker excursion of the vibrating diaphragm offset of detection dynamic loudspeaker or displacement
Survey device.The method and apparatus that vibrating diaphragm for detecting dynamic loudspeaker deviates are for for example related to vibrating diaphragm offset control or limitation
Many purposes be highly useful.Vibrating diaphragm offset control can be used for preventing vibrating diaphragm and Voice coil assemblies from being held beyond its maximum by driving
Perhaps peakdeviation.Unless take appropriate precautionary measures, powerful amplifier can force such high level driving current to voice coil, this
Vibrating diaphragm and Voice coil assemblies are made to exceed its maximum allowable peakdeviation by driving, so as to cause various mechanical failures.Therefore, it is necessary to supervise
The immediate movement of control/detection diaphragm of loudspeaker is to prevent the offset limitation by deviating the type for being more than the dynamic loudspeaker just discussed
Caused mechanical failure.The problem is such as the high-power loudspeaker of public address system, auto loud hailer and family Hi-
Many necks of the mini loud speaker of Fi applications and the portable communication appts for smart phone, laptop computer etc.
It is most important in the loudspeaker techniques in domain.
Many trials have been carried out in the prior art to detect or estimate the diaphragm of loudspeaker for the above purpose
Immediate movement.These trials are often based on the complicated nonlinear model of the particular speaker just discussed.Mode based on model
It is required that carefully analyzing the electric mechanical and magnetic properties of interested particular speaker type.Similarly, the mode based on model
It is required that the complicated real-time calculating on non-linear speaker model is to estimate the actual shifts of the loud speaker really operated.Complicated
Calculating causes the high power consumption of digital signal processor (it executes estimation and/or control algolithm based on model), this is for such as intelligence
The battery powered communication device of energy phone etc. is especially undesirable.In addition, model parameter is difficult to accurately to determine and can be with
It temperature, time and changes between the independent loud speaker sample of same type.Other trials have been based on is shaken by being attached to
The transducer signal of the various types of acceleration and velocity sensor of film or voice coil supply.
Therefore it provides the displacement or offset for estimating or detecting the diaphragm of loudspeaker are without depending on particular speaker class
The relatively simple method of the complicated nonlinear model of type is extremely important and valuable.If vibrating diaphragm displacement is more than to raise
The maximum allowable peakdeviation of sound device, then displacement detecting can be by adjoint for limiting the suitable mechanism of vibrating diaphragm displacement.It shakes
Film offset detection mechanism and corresponding detector should preferably use the elder generation of minimum or without loud speaker linear and nonlinear attribute
The knowledge tested and operate to simplify or completely eliminate calibration process.
2 453 670 A1 of EP, which disclose to generate in loudspeaker control system, can be used for mechanical loud speaker protection or uses
In method of the other signals preprocessing function without the control signal of the mechanical parameter knowledge of loud speaker.It can be to raise to control signal
Sound device be driven to its mechanical displacement limitation and the input voltage based on the so-called frequency dependence arbitrarily scaled to deviate pass
The measurement of the degree of closeness of delivery function.The latter's transmission function is during calibration process from the loud speaker in different audio frequencies
Multiple driving voltages and current measurement and export.
2009/268918 A1 of the U.S. is disclosed at the number using the immediate movement of the voice coil in speaker transducer
The mechanical protection of reason and the loud speaker of prediction estimation.The present invention by apply the linearly or nonlinearly fallout predictor based on foresight with
And it is operated directly on displacement signal finally to convert back the sound that the controller of the signal domain of input solves limitation energy converter
The problem of enclosing displacement.
With reference to figure 7,5,931,221 B1 of the U.S. discloses dynamic loudspeaker driving device, and the device is electronic including being coupled to
The power amplifier of loud speaker and feedback circuit for providing improved motion feedback.Feedback circuit negative-feedback is detected
Motional voltage is to power amplifier.Bridge circuit is for extracting the motional voltage generated by loud speaker.The branch of electric bridge includes impedance,
The impedance corresponds to the impedance of dynamic loudspeaker, this includes its movement resistance to provide more accurate motion feedback voltage.
Invention content
The first aspect of the present invention is related to detecting a kind of method of the vibrating diaphragm offset of dynamic loudspeaker comprising following step
Suddenly：
Generate the audio signal of the voice coil applied to dynamic loudspeaker.
High frequency probe signal is increased into the audio signal to generate composite drive signal,
Apply the composite drive signal to the voice coil by output amplifier, the exploration letter of the voice coil is flowed through in detection
The modulation level of number electric current.
Technical staff will be appreciated that every in audio signal, high frequency probe signal, composite drive signal and probe signal electric current
It is a to be indicated by analog signal (such as voltage, electric current, charge etc.) or alternatively (such as suitably sampled by digital signal
Rate and resolution ratio are in binary-coded) and indicate.
In one aspect, the method that the present invention provides offset or the displacement of the vibrating diaphragm of detection dynamic loudspeaker, this method profit
With the relevant change of offset of the voice coil inductance of dynamic loudspeaker.The relevant inductance of the offset of voice coil is reflected in dynamic loudspeaker
Voice coil high-frequency resistance the relevant change of corresponding offset.The change of the high-frequency resistance can be in the real-time of dynamic loudspeaker
During operation voice coil is flowed through by increasing to audio signal and detecting preferably non-audible high frequency probe or pilot signal
Result of the level of the modulation of probe signal electric current as the high frequency probe signal component for the composite drive signal for being applied to voice coil
And it detects.By suitably exporting or composite drive signal is preferably applied to voice coil by power amplifier.Letter is soundd out by detecting
The modulation level of number electric current can detect the offset of dynamic loudspeaker.
The relevant inductance of offset and the high-frequency resistance back of the body of the voice coil of dynamic loudspeaker are discussed in detail with reference to Fig. 2 and Fig. 3
Mechanism afterwards.
Audio signal may include the suitable audio from all Source Musics, CD Player, network player, MP3 player
The voice and/or music of source supply.Audio-source may also comprise the Mike that real-time microphone signal is generated in response to the sound of input
Wind.
The skilled person will understand that the selected frequency of high frequency probe signal can depend on specific dynamic loudspeaker
Impedance operator and various other application limitations and significant changes.In an exemplary embodiment, high frequency probe signal includes
Frequency is in 10kHz or more, more preferably in the sine wave of 20kHz or more.The frequency of higher frequency probe signals is preferably sufficiently high with right
It is non-audible in audience or user.The non-audible characteristic of high frequency probe signal can be by exploration frequency in the audible of human auditory
On limitation (such as on about 20kHz) and cause or because loud speaker can not reproduce the apparent of probe signal frequency
Acoustic pressure.The frequency of high frequency probe signal can therefore significant changes；Major diameter woofer can not be generated in such as 1kHz
On apparent voice response so that the high frequency probe signal of the loud speaker of the type can be placed in 1kHz or slightly 1kHz it
On.On the other hand, the minor diameter gamut mini electric loud speaker for being used for portable communication appts or music player produces
The useful acoustic pressure of up to 15kHz or even 20kHz so that the high frequency probe signal of the loud speaker of the type is preferably disposed in
20kHz or slightly on 20kHz to keep non-audible in all scenario.In addition, high frequency probe signal can be also advantageously located at it
The voice coil impedance of middle loud speaker shows the frequency range of apparent induction behavior.This is advantageous level detection accuracy,
Due to providing the higher of the probe signal electric current of frequency significantly contributed for total voice coil impedance in non-linear voice coil inductance
Modulation.
Technical staff will be appreciated that the modulation level of probe signal electric current actual detection can in analog or digital domain with
Various modes and complete.In preferred embodiments, the detection of the modulation level of probe signal electric current includes the following steps：
The composite drive signal code of voice coil is flowed through in detection in response to composite drive signal,
Bandpass filtering composite drive signal code with audio signal components therein of decaying,
The modulation level of probe signal electric current is detected from the composite drive signal code of bandpass filtering.
The bandpass filtering of composite drive signal code can by the bandpass filtering suitable voltage proportional to voice coil electric current,
The signals such as electric current, charge are realized with depending on selected voice coil current detection mechanism generation probe signal electric current.Band logical is filtered
Wave is from composite drive signal code removal audio signal components and substantially only through probe signal component.Hereafter, letter is soundd out
The modulation level of number electric current can be by using the conventional method extraction composite drive signal electricity of such as peak value or average detection
The envelope of stream and finally detection probe signal electric current envelope signal modulation and detect.
The frequency of the filtering complex tone loop current of selection is preferably suitable to inhibit all other frequency component in addition to neighbouring high frequency
Those of probe signal.The large amplitude low frequency component of audio signal is intended to determine the offset of the diaphragm of loudspeaker, show as
Close to probe signal frequency AM sidebands and therefore keep main zero-decrement by the filtering that frequency selects.Therefore, band logical
The offset of the envelope waveform reflection vibrating diaphragm of the composite drive signal code of filtering.Therefore, an embodiment of this method relies on
In detection bandpass filtering probe signal electric current envelope to detect modulation level.The envelope can be by such as tradition AM demodulation techniques
Various mechanism and detect.The latter includes rectification and the low-pass filtering of the composite drive signal code of bandpass filtering.In other realities
It applies in scheme, the modulation level of the probe signal electric current of filtering can be by being applied to number by suitable bottom and top tracker
The envelope waveform of the filtering probe signal electric current of conversion and detect or estimate.
Composite drive signal supplied to the voice coil of dynamic loudspeaker can be advantageously pulse modulation to utilize impulse modulation
Amplifier high power conversion efficiency.The impulse modulation can be opened up by using the output amplifier of switchtype or D Class Types
It flutters (such as PDM or PWM output amplifiers) and completes.The class-D amplifier of latter type provide audio signal impulse density or
Pulse width modulation is to generate the composite drive signal for the format for being in modulation.Alternatively, output amplifier may include such as A classes or
The power amplifier topology of traditional non-switch of AB classes.The output impedance of power amplifier is preferably less than desired or mesh
The voice coil impedance of loud speaker is marked, relevant audio frequency range, such as 20Hz to 20kHz are run through.Therefore, technical staff will
Solve output amplifier output impedance can significant changes, this depends on the impedance operator of target dynamic loudspeaker just discussed.
In many useful embodiments of the present invention, the output impedance of output amplifier is less than 1.0 Ω, all such as less than 0.5 Ω or 0.1
Ω runs through related audio frequency range.These ranges of relatively small output impedance are by output device/crystal of output amplifier
Minimum power losses in pipe especially (such as have between 2 ohm and 8 ohm when being coupled to Low ESR dynamic loudspeaker
The loud speaker of nominal impedance in range) when.The output impedance of output amplifier is also preferably less than in the frequency of probe signal
1.0 Ω, all such as less than 0.5 Ω or 0.1 Ω.
In many useful embodiments of this method, audio signal can be generated in number format as the first sampling
First digital audio and video signals of rate.First sampling rate is preferably relatively low, such as less than 44.1kHz or be less than 32kHz
To reduce the power consumption of related digital processing device and circuit.However, D Class Types output amplifier topology proposed above
The requirement sample frequency more much higher than the first sampling rate is to provide effective conversion.Therefore, the method preferably includes
Generate first digital audio and video signals of the audio signal as the first sampling rate.The first digital audio and video signals are up-sampled to generate height
In the final digital audio and video signals of the final sampling rate of the first sampling rate.It finally, will final number in output amplifier
Audio signal preferably pulse density modulated or pulse width modulation.Final sampling rate can be higher than the first sampling rate 4 and 32
Between multiple.
The up-sampling of first digital audio and video signals to final digital audio and video signals preferably carries out adopting on one or more centres
Sample grade generates digital audio and video signals with the respective intermediate sample rate among first with final sampling rate.
According to the preferred embodiment of this method, high frequency probe signal is generated in number format to be soundd out as digital high frequency
Signal, and it is increased to the digital audio and video signals of intermediate sample rate or to one in final digital audio and video signals to generate
In the composite drive signal of number format.In the particularly advantageous modification of later embodiment, by high-frequency digital probe signal
Increase above the digital audio and video signals of the intermediate sample rate of the frequency at least twice of digital high frequency probe signal.Increasing number
The first digital audio and video signals are up-sampled before word high frequency probe signal on the Nyquist frequencies of digital high frequency probe signal
Intermediate sample rate digital audio and video signals be beneficial in numerous applications.Up-sampling operation allows audio signal generator
It supplies the first digital audio and video signals to operate with relatively low sample frequency or rate (such as 32kHz), although using relative high frequency
Digital probe signal (such as 40kHz) be on the Nyquist frequencies of the first digital audio and video signals.Audio signal is given birth to
The relatively low sampling rate grown up to be a useful person reduces its power consumption.The up-sampling of first digital audio and video signals can be for example in D proposed above
The modulator of class A amplifier A is partially completed, without spending additional digital processing hardware and its related power consumption.Technology people
Member is it will be appreciated that final number can be applied to by various types of signal quantizations and noise shaping in the modulator part of class-D amplifier
Word audio signal and/or to sandwich digit audio signal.
This method of detection vibrating diaphragm offset can be configured to limit or control vibrating diaphragm offset to prevent for each of loud speaker
Kind mechanical failure.Mechanical failure can be by the moveable loudspeaker assembly and such as magnetic circuit of such as voice coil, vibrating diaphragm or sound ring frame
Fixed component between collision cause.In such embodiment of this method, the latter includes the following steps：Compare
The default modulation level standard of the modulation level of probe signal electric current detected and such as modulation level threshold value.
If the modulation level of probe signal electric current detected and default modulation level matches criteria, such as more than modulation
Level threshold, then offset control can for example be completed by the level of attenuated audio signal by various mechanism.Audio signal
The decaying of level can be completed by the low frequency component for digital audio and video signals of selectively decaying, because the latter more likely drives
Loud speaker is deviated on limitation to it or the entire audible spectrum of broadband attenuation digital audio and video signals.
Modulation level standard or threshold value can determine with various ways, such as by the loud speaker just discussed
Previous measurement.The preferred embodiment of this method includes the following steps：
The inclined of dynamic loudspeaker is determined during calibration measurement on dynamic loudspeaker or the dynamic loudspeaker of same type
Limitation is moved,
Offset limitation corresponding to loud speaker determines and the modulation level of record probe signal electric current,
Default modulation level standard is obtained from the modulation level of the probe signal electric current in offset limitation recorded.
Default modulation level standard can be in that number format is stored in the loudspeaker excursion detection for implementing this vibrating diaphragm offset detection
The suitable data memory location of device.Alternatively, default modulation level standard is storable in the data storage of signal processor
In, it is such as operably coupled to the microprocessor or DSP of loudspeaker excursion detector, as being additionally described in detail below.
It in one embodiment, will be high with the pulse modulated integral operation of audio signal in D class output amplifiers
Frequency probe signal increases to audio signal.It therefore, can be in pulse modulated output amplifier by with scheduled carrier frequency
High frequency probe signal is increased to audio signal by audio signal modulation so that high frequency probe signal by carrier frequency component generate or
Including carrier frequency component.Therefore, high frequency probe signal includes pulse modulated carrier frequency component.The carrier frequency of the type
Component is inherently increased to the drive signal that loud speaker is supplied to by D class output amplifiers, although certain output filter can decline
Subtract the level of these carrier frequency components.Although the carrier frequency component is undesired in many cases, this is specific
Embodiment uses existing carrier frequency component to eliminate the generation of individual high frequency probe signal.Therefore, it preserves individual
Number or simulation probe signal generator and corresponding signal synthesizer cause this loudspeaker excursion detector and corresponding method
Complexity reduction.
Increase high frequency probe signal to audio signal can during the operation of vibrating diaphragm bias detecting method substantially continue into
Row does not continue (such as only in the period of the certain characteristics for meeting audio signal) progress.It, should according to preferred embodiment
Method includes the following steps：
Compare the level of the audio signal and scheduled threshold level,
Only when Audio Meter is more than scheduled threshold level, high frequency probe signal is increased into audio signal.
Therefore, when Audio Meter drops to scheduled threshold level or less, the increase of high frequency probe signal can be interrupted.At this
In embodiment, scheduled threshold level ensures that high frequency probe signal only has enough level or amplitude to force in audio signal
It is increased to audio signal in the case that the diaphragm of loudspeaker is close to its offset limitation or on its offset limitation.Interrupt high frequency examination
The number of making inquiries about can be used for minimize with the related possible audible noise of high frequency probe signal, especially if by high frequency probe
Signal is placed in audible frequency range.Alternatively, when Audio Meter drops to scheduled threshold level or less, it can
The level for the high frequency probe signal that decayed with certain factor (such as 20dB or more).
As suggested previously, this method at least partly can be carried out advantageously in the digital domain.In one embodiment, it tries
Signal code is visited to be sampled by A/D converter to provide sampling or digital probe signal electric current.Existing examination in the digital domain
Visit modulation electricity of the signal code certainly particularly suitable for DSP algorithm or application by being executed on previously discussed signal processor
Flat detection.Technical staff will be appreciated that probe signal electric current can be by any suitable voltage, electric current or the charge that are proportional to
Signal and indicate.
The second aspect of the present invention is related to the loudspeaker excursion detector for dynamic loudspeaker comprising：
Audio signal input end, the reception for the audio signal for being used to be supplied by audio signal source,
Probe signal source is used for the generation of high frequency probe signal,
Signal combiner, is configured to combining audio signals and high frequency probe signal to provide composite drive signal,
Output amplifier is configured to supply combination flooding in a pair of output terminals for the voice coil for being connected to dynamic loudspeaker
Dynamic signal,
Current detector is configured for detecting the composite drive for flowing through voice coil in response to the application of composite drive signal
Signal code,
Modulation detector is configured to determine the modulation level of the probe signal electric current of composite drive signal code.
The attribute of output amplifier is disclosed in detail above in association with corresponding bias detecting method.The output of D classes is put
Big device may include the half-bridge driver grade for having the single output end for being coupled to dynamic loudspeaker or have to be coupled to dynamic loudspeaker
The full-bridge of a pair of output terminals of respective side or terminal/H- bridge driver grades.
Technical staff will be appreciated that current detector may include various types of current sensors, such as be connected to output amplification
The current mirror of the output transistor of device or small sense resistor with loudspeaker voice coil series coupled.Composite drive signal code can
Therefore it is indicated by the sensing voltage of proportional/scaling.Latter voltage can be sampled by previously discussed A/D converter to allow
The processing of probe signal electric current in the digital domain and modulation detection.Loudspeaker excursion detector preferably includes to be coupled to compound
Drive signal current reception and filter output provide probe signal electric current bandpass filter, such as above in association with
The corresponding feature of bias detecting method and be discussed in detail.
The preferred embodiment of modulation detector includes that one output end being coupled in bandpass filter is tried with detecting
Visit the envelope detector of the modulation level of signal code.Envelope detector may include AM demodulators and in numeric field or analog domain
Middle work is such as discussed in detail in the corresponding feature above in association with bias detecting method.
Loudspeaker excursion detector may include vibrating diaphragm offset limiter to control and/or limit vibrating diaphragm offset to prevent machinery
Damage, is such as discussed in detail in the corresponding feature above in association with bias detecting method.Vibrating diaphragm offset limiter may include matching
Set the modulation level detected for comparing probe signal electric current with such as the modulation level threshold of previously discussed reason
The comparator of the default modulation level standard of value.If vibrating diaphragm offset limiter is preferably arranged to examining for probe signal electric current
The modulation level of survey and default modulation level matches criteria (such as more than modulation level threshold value), then the electricity of attenuated audio signal
It is flat.
Audio signal source and probe signal source can be configured to supply audio signal and the high frequency examination in number format respectively
The digital complex drive signal of first sampling rate to be supplied to the work pulse width of pulse density modulated to modulate by the number of making inquiries about
The input terminal of power stage.
According to preferred embodiment, output amplifier includes being configured for receiving and up-sampling the first digital audio and video signals
Extremely higher than the final digital audio and video signals of the final sampling rate of the first sampling rate to generate the number of digital complex drive signal
Word up-samples circuit.Digital up-sampled circuit includes being configured to generate among the first sampling rate and final sampling rate
The one or more of one or more digital audio and video signals of respective intermediate sample rate is intermediate to up-sample grade.Therefore, in this
Between each of sampling rate or medium rates higher than the first sampling rate and be less than final sampling rate.In this loudspeaker excursion
In the particularly advantageous embodiment of detector, probe signal source is configured to generate high frequency probe signal as digital high frequency examination
The number of making inquiries about, and digital up-sampled circuit includes being configured to the digital high frequency probe signal increasing above digital high frequency
The digital signal combiner of the digital audio and video signals of the intermediate sample rate of the frequency at least twice of probe signal.The embodiment
It provides the advantage that and previously has been combined the first aspect of the present invention and be described in detail.
Final digital audio and video signals can be applied directly or indirectly to previously discussed pulse modulated output amplifier (example
Such as class-D amplifier) input terminal.
The third aspect of the present invention is related to the loudspeaker excursion integrated on it according to any of above embodiment
The semiconductor bottom plate or mold of detector.Semiconductor bottom plate can be used suitable CMOS or DMOS semiconductor technologies and manufacture.
The fourth aspect of the present invention is related to the deviation control system for dynamic loudspeaker.Deviation control system includes：
Dynamic loudspeaker comprising the moveable vibrating diaphragm group for generating audible sound in response to the actuating of the component
Part,
According to the loudspeaker excursion detector of any of the embodiment above, it is electrically coupled to moveable vibrating diaphragm
Component.Deviation control system further includes the audio letter for the audio signal input end for being operably coupled to loudspeaker excursion detector
Number source.Audio signal source may include programmable or hard-wired digital signal processor (DSP), operation particularly as
The digital audio source of this loudspeaker excursion detector.The digital audio and video signals supplied by programmable or hard-wired DSP
Can by DSP itself and generate or from be stored in be coupled to deviation control system readable data memory in audio file and examine
Rope.Digital audio and video signals may include the reality that DSP audio input ends are supplied to from the external digital audio-source of such as digital microphone
When digital audio and video signals.Real time digital audio signal can according to the standardized serial data communication protocol of such as IIC or SPI and
It formats, or according to such as I2S, the digital audio protocol of SPDIF etc. and format.
This deviation control system can be advantageously used for whole loudspeaker excursion detector and the audio of providing for oneself of control transmits
System, can in any specific environment and application processor independent operation with for dynamic loudspeaker offset induction machine
Tool damage provides reliable and convenient protection.
Description of the drawings
The preferred embodiments of the invention will be described in more detail in conjunction with attached drawing, wherein：
Fig. 1 is the schematic cross-sectional for closing the 6.5 " dynamic loudspeakers for being suitable for the invention various audio reproduction applications
View,
Fig. 2 shows the experiment experiment curv figure that the voice coil inductance of 6.5 " dynamic loudspeakers deviates vibrating diaphragm,
Fig. 3 shows the measured voice coil impedance versus frequency of dynamic loudspeaker shown in figure 1 above,
Fig. 4 is the schematic block according to the loudspeaker excursion detector of the dynamic loudspeaker of first embodiment of the invention
Figure,
Fig. 5 A) composite drive that the voice coil of dynamic loudspeaker is applied to by the loudspeaker excursion detector of figure 3 above is shown
Signal,
Fig. 5 B) show in response to above in Fig. 5 A) shown in composite drive signal application dynamic loudspeaker institute
The voice coil current waveform of the filtering of measurement,
Fig. 6 is shown above in Fig. 5 B) shown by filtering voice coil current waveform time-reversal mirror part.
Specific implementation mode
Fig. 1 is the signal diagram of the typical dynamic loudspeaker 100 in various types of voice applications.Technical staff
It will be appreciated that there are the shape and size of many dynamic loudspeakers, this depends on the desired type of institute of application.With being described below
The dynamic loudspeakers 100 of the method and apparatus detected and controlled for loudspeaker excursion there is about 6.5 inches of diaphragm diameter
D, but technical staff will be appreciated that the present invention substantially can be applied to all types of dynamic loudspeakers, especially in portable terminal
Small-sized electric of the end (such as mobile phone, smart phone and other portable music player devices) for audio reproduction is raised one's voice
Device.The largest outer dimension D of such mini electric loud speaker can be in 6mm between 30mm.
Dynamic loudspeaker 100 includes the vibrating diaphragm 10 for being fixed to sound ring frame 20a.Voice coil 20 be wrapped on sound ring frame 20a and
Firmly it is attached thereon.Vibrating diaphragm 10 is mechanically coupled to speaker frame 22 also by elastic edge or external suspension frame 12.Annular is forever
Long magnet arrangement 18 generates magnetic flux, which is passed by magnetic conduction construction 16 with the round air gap 24 arranged wherein
It leads.Circular ventilation ducts 14 are disposed in the center of magnetic conduction construction 16.Pipeline 14 can be used for heat being conducted off in vibrating diaphragm
10 and dustproof cover 11 under the room in addition sealed.Flexible internal suspension 13 is also attached to sound ring frame 20a.In flexible internal suspension
13 for being aligned or making the position of voice coil 20 at the center of air gap 24.Flexible internal suspension 13 and elastic edge suspension 12 cooperation with
The compliance of moveable vibrating diaphragm component (voice coil 20, sound ring frame 20a and vibrating diaphragm 10) preferably limited relatively is provided.Flexible internal
Each of suspension 13 and elastic edge suspension 12 can be used for limiting peak excursion or the maximum displacement of moveable vibrating diaphragm component.
During the operation of loud speaker 100, drive signal voltage is applied to the voice coil 20 of loud speaker 100.In response,
Corresponding voice coil electric current by incude cause in the piston range of loud speaker with the vibrating diaphragm group in the direction indicated by speed arrow V
The substantially uniform vibration motion of part.Corresponding acoustic pressure is generated by loud speaker 100 as a result,.In response to the flowing of voice coil electric current
The vibration action of voice coil 20 and vibrating diaphragm 10 is caused by radial oriented magnetic field present in air gap 24.The coil current applied
Lead to the power attenuation in voice coil 20 with voltage, this heats voice coil during operation.Therefore, the excessively high driving electricity of prolonged application
Pressure/electric current can cause voice coil to overheat, this typically results in the failure of dynamic loudspeaker or irreversible damage.Using excessive voice coil
It is the electricity for causing various irreversible mechanical failures that electric current, which forces moveable vibrating diaphragm component to be limited beyond its maximum allowable offset,
Another most common failure mechanism of dynamic loud speaker.A type of mechanical failure can for example by the lowermost edge of voice coil 20 with
Collision between the annular surface part 17 of magnetic conduction construction 16 causes.
The nonlinear main source of loud speaker 100 by the voice coil line in the magnetic field among being placed in magnetic gap 24 offset or displacement
Relevant length causes.It is illustrated from the signal of loud speaker 100, is arranged in neighbouring magnetic conduction construction 16 and tends to reduce the big of voice coil 20
Positive (upward) offset and the length of voice coil line of big negative offset of increase voice coil 20 be apparent.Due to close to have voice coil/
The variation of the amount of the permeability magnetic material of the voice coil of vibrating diaphragm offset, the inductance of voice coil 20 show the relevant variation of similar offset, this
Using in the present invention as explained in further detail below.
Fig. 2 shows the curves that the voice coil inductance of 6.5 " above-mentioned dynamic loudspeakers 100, Le measure the experiment that vibrating diaphragm deviates
Figure 200.Measured voice coil inductance is indicated with Henry along the y-axis of Fig. 2 and is referred to from the offset of the vibrating diaphragm of its resting position with mm
Show in x-axis.The resting position (and therefore resting position of Voice coil assemblies) of vibrating diaphragm corresponds to x=0.Any of resting position
The symmetry obviously lacked in inductance curve on side is apparent.Inductance increases negative displacement (inside) and reduces positive displacement
(outside).The shortage of the symmetry is caused by the apparent asymmetric geometry of the adjacent magnetic circuit of air gap 24.
Fig. 3 is shown across from 10Hz to the measured resistance of the above-mentioned 6.5 " dynamic loudspeakers of the frequency range of about 100kHz
Anti- curve 305.The loud speaker produces useful in certain subrange of the frequency range such as between about 50Hz and 10kHz
Acoustic pressure, this depends on the shape of the size and the diaphragm of loudspeaker of loudspeaker enclosure among others.The voice coil of loud speaker
About 3.5 Ω of DC resistance, as confirmed by measured 10Hz impedances.The low frequency or natural resonant frequency of loud speaker are located at
About 50Hz, middle impedance 303 reach about 50 Ω of low frequency peak value.On the natural resonant frequency of loud speaker, loudspeaker impedance
Curve 305 shows the impedance of constant rising, this is particularly evident for the frequency on about 3kHz.The rising of the impedance is by sound
The inductance of circle causes and continues the frequency to 100kHz for the loud speaker of inspection.Vertical arrows 308 illustrate by voice coil
Inductance LeThe high-frequency relevant voice coil resistance of non-linear shift/displacement caused by the relevant change variation of offset of explained earlier
It is anti-.Because of voice coil inductance LeTend to dominate voice coil impedance in the frequency field, so the voice coil inductance in voice coil impedance is inclined
Move the influence of relevant change becomes particularly evident in high-frequency.
Vertical arrows 304, vertical arrows 306 illustrate the impedance curve 305 of the relevant variation of temperature of the DC resistance of voice coil
On influence.Finally, horizontal arrow 307 illustrates the natural resonant frequency of the loud speaker 100 due to the change of suspension compliance
Temperature and the relevant variation of offset/displacement.
It is used by the present invention to detect vibrating diaphragm and sound in the high-frequency significant change with the voice coil impedance of vibrating diaphragm displacement
The offset of coil assembly.The variation of voice coil impedance is in selected frequency by the way that high frequency probe sound is increased to conventional audio signal
(such as voice and/or music) and formation pass through suitable low output impedance power amplifier (such as analog or digital D classes work(
Rate amplifier) be applied to loud speaker voice coil composite drive signal and measure.By detecting in response to composite drive signal
Application flow through voice coil probe signal electric current modulation degree or level, the offset of vibrating diaphragm and voice coil may be detected, such as existed
It explains in further detail below.
Fig. 4 show according to the first embodiment of the invention by a pair of outer can access loudspeaker terminal 411a,
Terminal 411b is coupled to the schematic block diagram of the loudspeaker excursion detector 400 of dynamic loudspeaker 100 discussed above.In this implementation
In scheme, loudspeaker excursion detector 400 operates in the digital domain, but other embodiments can instead of using analog signal or
Mixed analog and digital signal.Loudspeaker excursion detector 400 includes that audio signal input end In is used for by digital signal
Manage the reception of the digital audio and video signals of 402 supply of device (DSP).Therefore, DSP 402 is particularly useful as this loudspeaker excursion detector
400 digital audio source.The digital audio and video signals supplied by DSP 402 can be by DSP itself or from external digital audio-source
(such as digital microphone) and generate, and by audio input end 401 be supplied to DSP 402.The digital audio that outside generates
Signal can be formatted according to the standardized serial data communication protocol of such as IIC or SPI, or according to such as IIS, SPDIF
Deng digital audio protocol and format.From positive voltage VDDSupply loudspeaker excursion detector 400 operation power.Ground terminal
(not shown) or negative D/C voltage can form the negative supply voltage for loudspeaker excursion detector 400.D/C voltage VDDCan significantly it become
Change, this depends on the specific application of loudspeaker excursion detector 400, and is generally arranged between 1.5 volts and 100.0 volts
Voltage.
Technical staff will be appreciated that shown in loudspeaker excursion detector 400, DSP402 and loud speaker 100 can be formed for electricity
The part of the complete deviation control system of dynamic loud speaker 100.Particularly, DSP 402 and loudspeaker excursion detector 400 can integrate
A pair of outer shown in it can pass through accessible loudspeaker terminal 411a, terminal 411b are connected to public the half of loud speaker 100
On conductor substrate.DSP 402 is configured to the sample frequency of the 48kHz by being obtained from external DSP input end of clock f_clk1
Inter-process digital signal.External DSP input end of clock f_clk1 can be set to the frequency of the clock between 10MHz and 100MHz
Rate.It can be in other embodiments of the present invention according to the other performance characteristic of audio bandwidth as expected and specific application
Sample frequency is chosen to other frequencies of the frequency such as between 16kHz and 192kHz by factor.DSP402 is provided to raising one's voice
The digital audio and video signals of the input terminal of device offset detector 400 have the sample frequency of 48kHz.Loudspeaker excursion detector includes
It generates the previously discussed high frequency probe signal in number format and loudspeaker excursion detection is supplied to by terminal 403
The probe signal source (not shown) of device 400.Probe signal can be generated in identical sampling rate by DSP402 and be used as digital audio
Input signal is generated by independent digital probe signal source or generator with another sampling rate.
Loudspeaker excursion detector 400 includes digital PWM output amplifier comprising is coupled to answering for H bridges output stage 406
Close sampler and modulator 404.H bridges output stage will be in that pulse width is modulated by a pair of output terminals 411a, terminal 411b
The composite drive signal of format is supplied to loud speaker 100.Digital PWM output amplifier is configured to show in a pair of output terminals
Output impedance, this is substantially less than the impedance in the drive the speaker 100 of the frequency of digital probe signal with by substantially invariable electricity
Pressure driving is supplied to loud speaker 100 for the reason of discussing in further detail below.It is defeated in the digital PWM of probe signal frequency
The output impedance for going out amplifier is smaller than 1.0 Ω, even more preferably less than 0.5 Ω, all such as less than 0.1 Ω.
Loudspeaker excursion detector 400 further includes by arrow IsenseThe current detector of 407 signal diagrams, detection response
The combination flooding of the voice coil of loud speaker 100 is flowed through in the application of the composite drive signal of digital PWM output amplifier to loud speaker 100
Dynamic signal code IL.Technical staff will be appreciated that current detector may include various types of current sensors, generation and voice coil
In proportional voltage, electric current or the charge signal of composite drive signal code, such as be connected to the output transistor of H bridges 406
Current mirror or small sense resistor with 100 series coupled of loud speaker.Composite drive signal code ILIt can be therefore by being applied in
It is indicated to the sensing voltage of proportional/scaling of the input terminal of analog-digital converter 408.Analog-digital converter 408
Suitable for by measured sensing voltage digitlization and will be by the number of the fixed identical rate of analog-digital converter 408
Sensing voltage or sensing data are supplied to the suitable input port of DSP 402.The resolution ratio of analog-digital converter 408 can root
The exact value variation that must be indicated according to sensing voltage.In numerous applications, resolution ratio can drop between 8 bits and 24 bits.
In one embodiment, the sample frequency of analog-digital converter 408 is disposed above the frequency at least two of digital detection signal
Times frequency to ensure its Precise Representation without the mistake obscured.In this implementation of the probe signal frequency for having about 40kHz
In scheme, which means that the sample frequency of converter 408 should be greater than 80kHz, such as 96kHz.However, according to the present invention replace
For embodiment, the sample frequency of converter 408 is synchronous with digital probe signal so that the numeral output of converter 408 can be with
It is digitally processed with the spectral content of direct-down conversion or transposition composite drive signal code from frequency is soundd out to DC.This is directly
Frequency reducing conversion makes the envelope part of composite drive signal code be stopped centered on DC.This loudspeaker excursion detector 400 is somebody's turn to do
Embodiment allows to replace previously discussed analog or digital bandpass filter using wave digital lowpass filter to extract exploration letter
Number electric current.Another advantage of the embodiment for its permission after wave digital lowpass filter using digital decimation circuit or grade with
Sampling rate is reduced, so as to cause the lower MIPs requirements of lower digital power consumption and DSP 402.
DSP 402 preferably includes the DSP core of the software programmable by executable program instruction control so that each
Signal processing function can be implemented by the specific collection of executable program instruction.However, the skilled person will understand that alternatively, DSP
402 can be essentially hard-wired so that each signal processing function by specific collection configuration appropriate combination and/or sequence
Logic circuitry is implemented.
DSP 402 includes the modulation detector (not shown) that software or custom hardware are implemented, be configured to determine by
The V that proportional digital sensing voltage transmitssenseThe composite drive signal code I indicated to the input port of DSP 402LExamination
Visit the modulation level of signal code.As explained above, modulation detector is preferably implemented as executable program instructions collection.Hereafter
In conjunction with the composite drive signal code I in loud speaker 100LExperiment measure waveform explanation be further explained in detail exploration letter
The detection of the modulation level of number electric current.
As explained above, (rather than among DSP 402) will be counted among compound up-sampler and modulator 404
Word probe signal increases to digital audio and video signals, this causes certain benefits in many embodiments of the present invention.In this implementation
In scheme, digital probe signal has the frequency of about 40kHz, due to the specific high-frequency resistance characteristic of loud speaker 100.However,
Since DSP 402 is used to indicate digital audio and video signals using previously discussed internal sample rate 48kHz, so probe signal
Frequency is located on the Nyquist frequencies of DSP 402, makes DSP can not Precise Representation and the digital probe signal of manipulation.Although should
One solution of problem be for DSP 402 internal digital audio signal use higher sampling rate, but due to
The increase of adjoint power consumption, the solution is undesirable in some embodiments.The problem is in the present embodiment
Through by the way that digital probe signal is increased to existing for intermediate sample rate among compound up-sampler and modulator 404
Sandwich digit audio signal solves in an advantageous manner.The skilled person will understand that up-sampler or up-sampling circuit can be configured to
By the sampling rate of the 48kHz of digital audio and video signals increase scheduled integer or non-integer factor (such as between 4 and 32 because
Son), by up-sampling grade among one or more to generate sandwich digit audio signal.Preferred implementation side according to the present invention
Digital audio and video signals are up-sampled one or more cascaded stages, to provide in the centre of its respective intermediate sample rate by case
Digital audio and video signals.In an exemplary embodiment, up-sampling circuit is configured as 8: 1 up-samplings (factor 8) and wraps
Include three 2: 1 up-sampling grades of cascade or operation.Digital high frequency probe signal can be increased in any up-sampling grade, wherein centre or sheet
Ground sampling rate meets the Nyquist conditions for selecting probe signal frequency.Therefore, composite drive signal is in compound up-sampling
By the way that digital probe signal to be increased to the selected sandwich digit audio in intermediate sample rate among device and modulator 404
Signal and generate.Technical staff will be appreciated that various types of audio signals quantization of composite drive signal and noise shaping can apply
To form the drive signal of the final pulse width modulation for the input terminal for being applied to H bridges 406 in modulator part.
Finally, the skilled person will understand that as alternate embodiment of the invention, digital probe signal can be increased to
Digital audio and video signals among DSP 402.If the selected internal signal sampling rate of DSP402 is higher than from the beginning
The desired frequency of institute of digital high frequency probe signal is more than twice or is increasing internal signal sampling rate to adapt to digital high frequency
Probe signal is in acceptable situation, then this is of special interest.
Fig. 5 A) oscillogram 500 show to raise by what a pair of outer of the loudspeaker excursion detector of figure 4 above can access
Sound device terminal 411a, terminal 411b are applied to the composite drive signal of the voice coil of dynamic loudspeaker 100.Composite drive signal includes
Alternately small/big 60Hz signal components, the variable level of this simulation low-frequency audio signal and the uniform amplitude of 40kHz are high
Frequency probe signal.The small level period of 60Hz causes the low offset of moveable Voice coil assemblies and thus voice coil inductance LePhase
To constant value, as explained above in association with Fig. 2 and Fig. 3.On the other hand, the 60Hz components of composite drive signal have high electricity
Flat period cause moveable Voice coil assemblies it is big offset and thus voice coil inductance LeRelatively large offset relevant change
Become, as explained above in association with Fig. 2.
40kHz loudspeaker excursion detector 400 output impedance significantly less than loud speaker 100 40kHz impedance
32 Ω (with reference to the impedance curve 305 described in Fig. 3).For example, the output impedance of the loudspeaker excursion detector 400 in 40kHz
It can be under 1.0 Ω so that the level of the substantial constant of composite drive signal driving voltage can be applied to loudspeaker voice coil,
This is independently of by voice coil inductance LeThe relevant change of offset caused by loud speaker previously described variable high frequency impedance.
If the 40kHz impedances of voice coil with loudspeaker excursion changes (i.e. as explained above moveable vibrating diaphragm with
The big offset of Voice coil assemblies), then the voltage driving for souning out the voice coil of the loud speaker of frequency in 40kHz causes through the bright of voice coil
The probe signal electric current of aobvious variation.In the case of opposite, the small offset for moveable vibrating diaphragm and Voice coil assemblies, because of sound
The 40kHz impedances of circle keep main constant but regardless of loudspeaker excursion, so the voice coil for souning out frequency in 40kHz obtains constant voltage
Driving causes the probe signal electric current by the substantial constant of voice coil.
The phenomenon is in Fig. 5 B) curve graph 502 shown on, show around audio drive signals 60Hz component height
The voice coil current waveform 505 of the bandpass filtering for the time-reversal mirror that level changes to low level.The voice coil current waveform 505 of filtering is
Through being obtained by by the band-pass filter centered on the probe signal frequency of 40kHz.When 60Hz drive signal components
Level when being big (i.e. from t=8.5s to 8.6s), the voice coil current waveform of discribed filtering is transparent to show that high level
Modulation, as indicated by the arrow 501 of the top and bottom of the envelope of the voice coil current waveform by tracking filter.In the region
The minimum and maximum amplitude of the probe signal electric current of filtering corresponds to the maximum value and minimum value of 60Hz input signals.On the contrary,
As by the low level modulation indicated by arrow 503 the 60Hz drive signal components from t=8.6s to 8.85s low level situation
Under be apparent.Therefore, by the envelope modulation of the voice coil current waveform of detection filter, moveable vibrating diaphragm component can be detected
Displacement.Technical staff will be appreciated that the actually detected of the modulation level of probe signal electric current can be in analog or digital domain with various sides
Formula is completed, such as traditional AM demodulation techniques by including signal rectification and low-pass filtering.In other embodiments, can lead to
Cross by suitable bottom and top tracker be applied to curve graph 502 filtering voice coil current waveform and detect or estimate exploration
The modulation level of signal code.This can pass through in numeric field by the probe signal electric current supplied by analog-digital converter 508
Suitable software function that the DSP 402 (with reference to Fig. 4) that is operated on the digitized version of waveform is executed and complete.
DSP 402 can be otherwise configured to limit or control vibrating diaphragm offset in addition to the detection of above-mentioned vibrating diaphragm/voice coil excursion.It should
Offset control can be completed by number of mechanisms.In one embodiment, the maximum allowable offset of dynamic loudspeaker is raised electronic
It is determined during calibration measurement on sound device or the dynamic loudspeaker of same type.Corresponding to the probe signal of maximum allowable offset
The modulation level of electric current is registered as maximum modulation threshold value or similar modulation level standard.In loudspeaker excursion detector 400
Subsequent operation during, the instantaneous modulation level of probe signal electric current and run on DSP 402 appropriately configured software/
The maximum modulation threshold value of program routine is made comparisons.If the instantaneous modulation level of probe signal electric current is more than maximum modulation threshold
Value, then for example (this more has can by the low frequency component for digital audio input signal of selectively decaying by DSP 402 in response
Can on drive the speaker limits to its maximum allowable offset) or the entire frequency spectrum of broadband attenuation digital audio input signal decline
The level of tally-down audio input signal is to loudspeaker excursion detector 400.
Finally, the skilled person will understand that the 40kHz frequencies that the frequency of high frequency probe signal can be utilized from the present embodiment
Rate deviates considerably from, this depends on the impedance operator of specific dynamic loudspeaker.In addition, the frequency of high frequency probe signal should preferably enough
It is high so that its present it is non-audible, either because frequency be located at human auditory can on cingulum (i.e. on 20kHz) or
Because loud speaker can not be reproduced in the apparent acoustic pressure of probe signal frequency.Therefore the selection of probe signal frequency can significantly become
Change, this depends on the acoustics and electrology characteristic of the speaker types just discussed；Major diameter woofer can not be generated for example
Voice response on 1kHz so that the high frequency probe signal of the loud speaker of the type can be placed in 1kHz or slightly 1kHz it
On.On the other hand, the minor diameter gamut mini electric loud speaker for being used for portable communication appts or music player produces
The significant acoustic pressure of up to 15kHz or even 20kHz so that the high frequency probe signal of the loud speaker of the type should be preferably disposed in
20kHz or slightly on 20kHz to keep non-audible.In addition, high frequency probe signal can be also advantageously located at the sound of wherein loud speaker
Circle impedance shows the frequency range of apparent induction behavior.This is preferably as bias detecting method and device are to be based on sound
Enclose inductance LeThe relevant behavior of above-mentioned offset.
Fig. 6 shows to correspond to Fig. 5 B) curve graph 502 measured waveform 505 filtering voice coil current waveform
The simulation of time-reversal mirror, but it is removable to prevent for wherein for example having been contacted by the magnetic circuit construction machine with loud speaker
The case where dynamic vibrating diaphragm component further deviates.With reference to figure 1, which corresponds at the lowermost edge and magnetic conduction of voice coil 20
Discussed collision between the annular surface part 17 of structure 16.Present inventor have determined that the voice coil current waveform of filtering
Certain features have reached or for detecting the moveable vibrating diaphragm component of loud speaker more than its maximum allowable offset or offset limit
System is highly useful.Therefore, unless preventative action is taken to limit offset, the mechanical failure of voice coil is possible result.It should
Determination can from voice coil current waveform of filtering itself without the loud speaker just discussed linear and nonlinear attribute it is any
Priori and the fact that make are highly useful.This feature can eliminate what previously discussed deviation control system was extremely connected
The needs of dynamic loudspeaker individually calibrated.
Envelope of the shown section of the voice coil current waveform of filtering on Figure 60 0 around the voice coil current waveform of filtering
Single peak value centered on.Shown voice coil current waveform 605 includes substantially flat peak value platform, such as by dotted line frame
Indicated by 607.Change in the simulation of the voice coil inductance of percentage and is indicated along y-axis by curve 601.Curve 601 also shows base
Flat peak value platform in sheet, as indicated by dotted line frame 603.The unexpected stopping of the change of the offset induction of voice coil inductance refers to
Show that the offset of moveable vibrating diaphragm component (to voice coil) stops suddenly in an identical manner, such as passes through institute such as above
The collision with magnetoelectricity line structure proposed.Definitely when the moveable vibrating diaphragm component of loud speaker alreadys exceed its offset limitation
Detection can be carried out by these the substantially flat peak value platforms being originally identified in voice coil current waveform 605.Hereafter,
The shape of current waveform 605 can waveform shape corresponding with speaker drive voltage be associated, such as believed by audio input
Number waveform and indicate.If the position of flat peak value platform of the speaker drive voltage in voice coil current waveform 605 is not
With corresponding flat peak value platform, which indicates that the discussed above of the offset of moveable vibrating diaphragm component is stopped suddenly
It is stagnant.
The period of the non-zero instruction voice coil current waveform 605 of rectangular lines 609, wherein moveable vibrating diaphragm group
Part is estimated more than its offset limitation.The estimation passes through the phase based on voice coil current waveform 605 and speaker drive voltage
The detection of the flat peak value platform of contact calculates applying technology proposed above.
Claims (32)
1. a kind of method of the vibrating diaphragm offset of detection dynamic loudspeaker comprising the following steps：
The audio signal of the voice coil applied to the dynamic loudspeaker is generated,
High frequency probe signal is increased into the audio signal to generate composite drive signal,
The composite drive signal is applied to the voice coil by output amplifier,
Detect the modulation level for the probe signal electric current for flowing through the voice coil in response to the application of the composite drive signal.
2. the method for the vibrating diaphragm offset of detection dynamic loudspeaker according to claim 1, wherein the probe signal electric current
The detection of the modulation level include the following steps：
The composite drive signal code of the voice coil is flowed through in detection in response to the composite drive signal,
Composite drive signal code described in bandpass filtering with audio signal components therein of decaying,
The modulation level of the probe signal electric current is detected from the composite drive signal code of the bandpass filtering.
3. the method for the vibrating diaphragm offset of detection dynamic loudspeaker according to claim 1, wherein the probe signal electric current
The detection of the modulation level include：
Detect the envelope of the probe signal electric current.
4. the method for the vibrating diaphragm offset of detection dynamic loudspeaker according to claim 2, wherein detecting the probe signal
The modulation level of electric current includes：
The composite drive signal code of bandpass filtering described in rectification and low-pass filtering.
5. the method for the vibrating diaphragm offset of detection dynamic loudspeaker according to claim 1 comprising the following steps：
Pulse density modulated or pulse width modulate the audio signal with by PDM or PWM modulation in the output amplifier
Composite drive signal respectively be supplied to the dynamic loudspeaker the voice coil.
6. the method for the vibrating diaphragm offset of the detection dynamic loudspeaker according to any one of claim 1-5 comprising under
Row step：
First digital audio and video signals of the audio signal as the first sampling rate are generated, first digital audio is up-sampled
Signal with generate be higher than first sampling rate final sampling rate final digital audio and video signals,
Pulse density modulated or pulse width modulate the final digital audio and video signals in the output amplifier.
7. the method for the vibrating diaphragm offset of detection dynamic loudspeaker according to claim 6 comprising the following steps：
Will the one or more intermediate up-sampling grades of first digital audio and video signals up-sampling with first sampling rate with
Respective intermediate sample rate among the final sampling rate generates digital audio and video signals.
8. the method for the vibrating diaphragm offset of detection dynamic loudspeaker according to claim 7 comprising the following steps：
The high frequency probe signal is generated as digital high frequency probe signal,
By the digital high frequency probe signal increase to the intermediate sample rate the digital audio and video signals or to it is described most
One in whole digital audio and video signals to generate the composite drive signal in number format.
9. the method for the vibrating diaphragm offset of detection dynamic loudspeaker according to claim 8, wherein the digital high frequency is tried
The number of making inquiries about increases above the digital audio letter of the intermediate sample rate of the frequency at least twice of the digital high frequency probe signal
Number.
10. the method for the vibrating diaphragm offset of detection dynamic loudspeaker according to claim 1 comprising the following steps：
Compare the modulation level of the detection of the probe signal electric current and preset modulation level standard.
11. the method for the vibrating diaphragm offset of detection dynamic loudspeaker according to claim 10 comprising the following steps：
If the modulation level of the detection of the probe signal electric current and the preset modulation level matches criteria,
Decay the Audio Meter.
12. the method for the vibrating diaphragm offset of detection dynamic loudspeaker according to claim 1, wherein the high frequency probe signal
Including frequency 10kHz or more sine wave.
13. the method for the vibrating diaphragm offset of detection dynamic loudspeaker according to claim 1 comprising the following steps：
The high frequency is tried with scheduled carrier frequency by modulating the audio signal in pulse modulated output amplifier
The number of making inquiries about increases to the audio signal so that the high frequency probe signal includes carrier frequency component.
14. the method for the vibrating diaphragm offset of detection dynamic loudspeaker according to claim 1 comprising the following steps：
The Audio Meter is detected,
Compare the level of the audio signal and scheduled threshold level, only when the level of the audio signal is more than
When the scheduled threshold level, the high frequency probe signal is increased into the audio signal.
15. the method for the vibrating diaphragm offset of detection dynamic loudspeaker according to claim 1 comprising the following steps：
The dynamic loudspeaker is determined during calibration measurement on the dynamic loudspeaker or the dynamic loudspeaker of same type
Offset limitation,
Determine and record the modulation electricity of the probe signal electric current of the offset limitation corresponding to the loud speaker
It is flat,
Default modulation level mark is obtained from the modulation level of the record of the probe signal electric current in the offset limitation
It is accurate.
16. the method for the vibrating diaphragm offset of detection dynamic loudspeaker according to claim 1 comprising the following steps：
The probe signal electric current is sampled to provide sampling or digital probe signal electric current with A/D converter.
17. the method for the vibrating diaphragm offset of detection dynamic loudspeaker according to claim 11, wherein the probe signal is electric
The modulation level of the detection of stream includes with the preset modulation level matches criteria：More than modulation level threshold value.
18. a kind of loudspeaker excursion detector for dynamic loudspeaker comprising：
Audio signal input end, the reception for the audio signal for being used to be supplied by audio signal source,
Probe signal source is used for the generation of high frequency probe signal,
Signal combiner is configured to combine the audio signal with the high frequency probe signal to provide composite drive letter
Number,
Output amplifier is configured to supply the combination flooding in a pair of output terminals for the voice coil for being connected to dynamic loudspeaker
Dynamic signal,
Current detector is configured for detecting in response to the application of the composite drive signal and flowing through answering for the voice coil
Drive signal current is closed,
Modulation detector is configured to determine the modulation level of the probe signal electric current of the composite drive signal code.
19. loudspeaker excursion detector according to claim 18 comprising：It is coupled to the composite drive signal electricity
Stream receives and provides the bandpass filter of the probe signal electric current in filter output.
20. loudspeaker excursion detector according to claim 19, wherein the modulation detector is described including being coupled to
The output end of bandpass filter is to detect the envelope detector of the modulation level.
21. loudspeaker excursion detector according to claim 18, wherein the output amplifier include be configured to by
D class power stage of the pulse modulated composite drive signal supplied to the voice coil of the dynamic loudspeaker.
22. loudspeaker excursion detector according to claim 21 exists wherein the audio signal source is configured to supply
The audio signal in number format of first sampling rate is as the first digital audio and video signals；And
The output amplifier includes digital up-sampled circuit, is configured for receiving and up-sampling first digital audio
Signal is to the final digital audio and video signals of the final sampling rate higher than first sampling rate to generate digital complex driving
Signal.
23. loudspeaker excursion detector according to claim 22, wherein digital up-sampled circuit include being configured to give birth to
At one or more numbers of the respective intermediate sample rate among first sampling rate and the final sampling rate
The one or more of word audio signal is intermediate to up-sample grade.
24. loudspeaker excursion detector according to claim 23, wherein the probe signal source is configured to generate institute
State digital high frequency probe signal of the high frequency probe signal as the second sampling rate；And
The digital up-sampled circuit treasure-house digital signal combiner is configured to increase the digital high frequency probe signal
To the digital audio and video signals of the intermediate sample rate of the frequency at least twice higher than the digital high frequency probe signal.
25. loudspeaker excursion detector according to claim 23, wherein the output amplifier includes being coupled to institute
State the pulse density modulated of the reception of the final digital audio and video signals of final sampling rate and pulse width modulation work(
One in rate grade.
26. loudspeaker excursion detector according to claim 18 comprising：
Comparator is configured for the modulation level of the detection of probe signal electric current described in comparison and default modulation level
Standard.
27. loudspeaker excursion detector according to claim 26 comprising：
Vibrating diaphragm deviates limiter, if be configured to the modulation level of the detection of the probe signal electric current with it is described pre-
If modulation level matches criteria, then the Audio Meter of decaying.
28. loudspeaker excursion detector according to claim 22, wherein the current detector include A/D converter with
The sampling for indicating the composite drive signal code or digital signal is provided.
29. loudspeaker excursion detector according to claim 18, wherein the output amplifier is included in the exploration
The scheduled output impedance less than 1.0 Ω of signal frequency.
30. a kind of semiconductor bottom plate has loudspeaker excursion detector according to claim 18 integrated on it.
31. a kind of deviation control system for dynamic loudspeaker comprising：
Dynamic loudspeaker comprising moveable vibrating diaphragm component, the moveable vibrating diaphragm component are used in response to described removable
The actuating of dynamic vibrating diaphragm component generates audible sound,
Loudspeaker excursion detector according to claim 18 is electrically coupled to the moveable vibrating diaphragm component,
Audio signal source is operably coupled to the audio signal input end of the loudspeaker excursion detector.
32. the deviation control system according to claim 31 for dynamic loudspeaker, wherein the audio signal source packet
Transmission digital audio and video signals are included to the DSP of the loudspeaker excursion detector.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US13/779,314 US10219090B2 (en) | 2013-02-27 | 2013-02-27 | Method and detector of loudspeaker diaphragm excursion |
| US13/779,314 | 2013-02-27 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN104010263A CN104010263A (en) | 2014-08-27 |
| CN104010263B true CN104010263B (en) | 2018-07-17 |
Family
ID=50156642
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201410065381.1A Active CN104010263B (en) | 2013-02-27 | 2014-02-26 | Method and detector for diaphragm of loudspeaker offset |
Country Status (3)
| Country | Link |
|---|---|
| US (1) | US10219090B2 (en) |
| EP (1) | EP2773132B1 (en) |
| CN (1) | CN104010263B (en) |
Families Citing this family (40)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9161126B2 (en) * | 2013-03-08 | 2015-10-13 | Cirrus Logic, Inc. | Systems and methods for protecting a speaker |
| GB201418782D0 (en) * | 2013-10-25 | 2014-12-03 | Tymphany Worldwide Entpr Ltd | Low profile loudspeaker transducer |
| EP2890160B1 (en) | 2013-12-24 | 2019-08-14 | Nxp B.V. | Loudspeaker controller |
| US9959716B2 (en) | 2014-02-13 | 2018-05-01 | Nxp B.V. | Multi-tone haptic pattern generator |
| DE102014101881B4 (en) * | 2014-02-14 | 2023-07-27 | Intel Corporation | Audio output device and method for determining speaker cone excursion |
| US9992596B2 (en) | 2014-11-28 | 2018-06-05 | Audera Acoustics Inc. | High displacement acoustic transducer systems |
| FR3031854B1 (en) * | 2015-01-19 | 2017-02-17 | Devialet | DEVICE FOR CONTROLLING A LOUDSPEAKER WITH CURRENT LIMITATION |
| CN105992097B (en) * | 2015-01-29 | 2020-05-26 | 联想(北京)有限公司 | Audio processing method and audio processing device |
| US10034109B2 (en) | 2015-04-09 | 2018-07-24 | Audera Acoustics Inc. | Acoustic transducer systems with position sensing |
| US9565505B2 (en) * | 2015-06-17 | 2017-02-07 | Intel IP Corporation | Loudspeaker cone excursion estimation using reference signal |
| CN105120414B (en) * | 2015-08-04 | 2018-05-11 | 深圳英集芯科技有限公司 | Intelligent audio management system |
| US10581386B2 (en) * | 2015-12-25 | 2020-03-03 | Panasonic Intellectual Property Management Co., Ltd. | Protective device |
| US10547942B2 (en) | 2015-12-28 | 2020-01-28 | Samsung Electronics Co., Ltd. | Control of electrodynamic speaker driver using a low-order non-linear model |
| TWI587711B (en) * | 2016-03-15 | 2017-06-11 | 瑞昱半導體股份有限公司 | Device and method of calculating excursion of diaphragm of loudspeaker and method of controlling loudspeaker |
| US10728659B2 (en) * | 2016-05-02 | 2020-07-28 | Purifi Aps | Method of controlling loudspeaker diaphragm excursion |
| US9955256B2 (en) * | 2016-06-28 | 2018-04-24 | Cirrus Logic, Inc. | Speaker protection based on output signal analysis |
| US10374566B2 (en) * | 2016-07-29 | 2019-08-06 | Maxim Integrated Products, Inc. | Perceptual power reduction system and method |
| CN109937581B (en) | 2016-11-21 | 2021-10-29 | 罗伯特·博世有限公司 | Loudspeaker with multi-stage suspension system |
| US10341767B2 (en) * | 2016-12-06 | 2019-07-02 | Cirrus Logic, Inc. | Speaker protection excursion oversight |
| US10462565B2 (en) | 2017-01-04 | 2019-10-29 | Samsung Electronics Co., Ltd. | Displacement limiter for loudspeaker mechanical protection |
| GB2561022B (en) * | 2017-03-30 | 2020-04-22 | Cirrus Logic Int Semiconductor Ltd | Apparatus and methods for monitoring a microphone |
| GB2563460B (en) * | 2017-06-15 | 2021-07-14 | Cirrus Logic Int Semiconductor Ltd | Temperature monitoring for loudspeakers |
| EP3448059A1 (en) * | 2017-08-22 | 2019-02-27 | Nxp B.V. | Audio processor with temperature adjustment |
| EP3603116A1 (en) | 2017-12-15 | 2020-02-05 | Google LLC. | Inductive excursion sensing for audio transducers |
| US10506347B2 (en) * | 2018-01-17 | 2019-12-10 | Samsung Electronics Co., Ltd. | Nonlinear control of vented box or passive radiator loudspeaker systems |
| US10701485B2 (en) | 2018-03-08 | 2020-06-30 | Samsung Electronics Co., Ltd. | Energy limiter for loudspeaker protection |
| CN108471575B (en) * | 2018-05-14 | 2020-07-03 | 广东小天才科技有限公司 | Liquid discharge method for loudspeaker of mobile terminal and mobile terminal |
| US10542361B1 (en) | 2018-08-07 | 2020-01-21 | Samsung Electronics Co., Ltd. | Nonlinear control of loudspeaker systems with current source amplifier |
| US11012773B2 (en) | 2018-09-04 | 2021-05-18 | Samsung Electronics Co., Ltd. | Waveguide for smooth off-axis frequency response |
| US10797666B2 (en) | 2018-09-06 | 2020-10-06 | Samsung Electronics Co., Ltd. | Port velocity limiter for vented box loudspeakers |
| CN109495820B (en) * | 2018-12-07 | 2021-04-02 | 武汉市聚芯微电子有限责任公司 | Amplitude adjusting method and system for loudspeaker diaphragm |
| CN113615211B (en) * | 2019-01-10 | 2023-09-08 | 零件快递国际公司 | Measuring non-linearities and asymmetries of loudspeakers |
| US11546709B2 (en) * | 2019-09-23 | 2023-01-03 | Texas Instruments Incorporated | Audio playback under short circuit conditions |
| US10771893B1 (en) * | 2019-10-10 | 2020-09-08 | xMEMS Labs, Inc. | Sound producing apparatus |
| CN111083609B (en) * | 2019-12-06 | 2021-11-26 | 歌尔股份有限公司 | Voice coil wire, voice coil and sound production device for sound production device |
| US11102575B1 (en) * | 2020-02-05 | 2021-08-24 | Tymphany Acoustic Technology Limited | Loudspeaker with passively controlled voice coil sections |
| GB2595234B (en) | 2020-05-18 | 2022-06-01 | Waves Audio Ltd | Control of an electrostatic acoustic device |
| US11356773B2 (en) | 2020-10-30 | 2022-06-07 | Samsung Electronics, Co., Ltd. | Nonlinear control of a loudspeaker with a neural network |
| CN115562956B (en) * | 2021-07-01 | 2023-09-19 | 腾讯科技（深圳）有限公司 | Vibration evaluation method, vibration evaluation device, computer device, and storage medium |
| CN116896713B (en) * | 2023-09-04 | 2023-12-05 | 立臻精密智造(昆山)有限公司 | Device and method for determining height of loudspeaker diaphragm |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2453670A1 (en) * | 2010-11-16 | 2012-05-16 | Nxp B.V. | Control of a loudspeaker output |
| CN102802104A (en) * | 2012-08-16 | 2012-11-28 | 何永斌 | Moving-coil loudspeaker with area-alterable capacitive vibration sensor |
Family Cites Families (37)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3875341A (en) * | 1972-02-24 | 1975-04-01 | Int Standard Electric Corp | System for transferring wideband sound signals |
| CA1195133A (en) * | 1982-01-29 | 1985-10-15 | James J. Mckenna | Circular locking device |
| JPS59140739A (en) * | 1983-01-31 | 1984-08-13 | Sony Corp | Control signal detecting circuit |
| US5031221A (en) | 1987-06-02 | 1991-07-09 | Yamaha Corporation | Dynamic loudspeaker driving apparatus |
| US5548650A (en) | 1994-10-18 | 1996-08-20 | Prince Corporation | Speaker excursion control system |
| GB9513894D0 (en) | 1995-07-07 | 1995-09-06 | Univ Salford The | Loudspeaker circuit |
| US5613218A (en) * | 1995-08-28 | 1997-03-18 | Motorola, Inc. | Method and apparatus in a radio communication system for mitigating noise and interference effects |
| EP0860675A3 (en) | 1997-02-21 | 1999-08-11 | Zexel Corporation | Heat exchanger |
| US6122380A (en) * | 1997-12-01 | 2000-09-19 | Sony Corporation | Apparatus and method of providing stereo television audio signals |
| DE19804992C1 (en) | 1998-02-07 | 1999-08-19 | Mantel | Loudspeaker drive circuit |
| JP2001169384A (en) * | 1999-12-10 | 2001-06-22 | Pioneer Electronic Corp | Speaker system |
| JP2003037887A (en) | 2001-07-25 | 2003-02-07 | Mitsubishi Electric Corp | Acoustic controller and acoustic system |
| US20040022409A1 (en) | 2002-05-02 | 2004-02-05 | Hutt Steven W. | Film attaching system |
| US6940981B2 (en) | 2003-03-12 | 2005-09-06 | Qsc Audio Products, Inc. | Apparatus and method of limiting power applied to a loudspeaker |
| US20060172716A1 (en) * | 2003-03-14 | 2006-08-03 | Matsushita Electric Industrail Co., Ltd. | Ofdm reception device and ofdm reception method |
| JP4197293B2 (en) | 2003-12-10 | 2008-12-17 | パナソニック株式会社 | A / D converter, D / A converter |
| US7372966B2 (en) | 2004-03-19 | 2008-05-13 | Nokia Corporation | System for limiting loudspeaker displacement |
| CA2600196A1 (en) * | 2004-03-29 | 2005-10-20 | Peter T. German | Systems and methods to determine elastic properties of materials |
| US7106865B2 (en) * | 2004-12-15 | 2006-09-12 | Motorola, Inc. | Speaker diagnostics based upon driving-point impedance |
| US20070041606A1 (en) * | 2005-08-22 | 2007-02-22 | David Clark Company Incorporated | Apparatus and method for noise cancellation in communication headset using dual-coil speaker |
| ATE458362T1 (en) | 2005-12-14 | 2010-03-15 | Harman Becker Automotive Sys | METHOD AND APPARATUS FOR PREDICTING THE BEHAVIOR OF A TRANSDUCER |
| US7298296B1 (en) * | 2006-09-02 | 2007-11-20 | Cirrus Logic, Inc. | Real-time sample rate converter having a non-polynomial convolution kernel |
| US7791427B2 (en) * | 2007-08-30 | 2010-09-07 | D2Audio Corporation | Systems and methods to minimize startup transients in class D amplifiers |
| TWI351717B (en) * | 2007-10-15 | 2011-11-01 | Univ Nat Chiao Tung | Method for forming group-iii nitride semiconductor |
| US9425747B2 (en) * | 2008-03-03 | 2016-08-23 | Qualcomm Incorporated | System and method of reducing power consumption for audio playback |
| US8712065B2 (en) | 2008-04-29 | 2014-04-29 | Bang & Olufsen Icepower A/S | Transducer displacement protection |
| EP2361476B1 (en) * | 2008-11-03 | 2015-06-03 | Brüel & Kjaer Sound & Vibration Measurement A/S | Test system with digital calibration generator |
| KR20120088258A (en) * | 2011-01-31 | 2012-08-08 | 삼성전자주식회사 | Method for outputting an audio signal and apparatus for outputting an audio signal thereof |
| JP2012186676A (en) | 2011-03-07 | 2012-09-27 | Sony Corp | Signal processing device and signal processing method |
| US8705754B2 (en) * | 2011-03-30 | 2014-04-22 | Bose Corporation | Measuring transducer displacement |
| US9837971B2 (en) * | 2011-05-04 | 2017-12-05 | Texas Instruments Incorporated | Method and system for excursion protection of a speaker |
| US8897465B2 (en) * | 2011-06-01 | 2014-11-25 | Robert Bosch Gmbh | Class D micro-speaker |
| EP2538699B1 (en) | 2011-06-22 | 2015-11-11 | Nxp B.V. | Control of a loudspeaker output |
| US20130077795A1 (en) * | 2011-09-28 | 2013-03-28 | Texas Instruments Incorporated | Over-Excursion Protection for Loudspeakers |
| DK2613566T3 (en) * | 2012-01-03 | 2016-10-17 | Oticon As | A listening device and method for monitoring the placement of an earplug for a listening device |
| US9173020B2 (en) | 2012-03-27 | 2015-10-27 | Htc Corporation | Control method of sound producing, sound producing apparatus, and portable apparatus |
| US9161126B2 (en) | 2013-03-08 | 2015-10-13 | Cirrus Logic, Inc. | Systems and methods for protecting a speaker |
-
2013
- 2013-02-27 US US13/779,314 patent/US10219090B2/en active Active
-
2014
- 2014-02-25 EP EP14156524.2A patent/EP2773132B1/en active Active
- 2014-02-26 CN CN201410065381.1A patent/CN104010263B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2453670A1 (en) * | 2010-11-16 | 2012-05-16 | Nxp B.V. | Control of a loudspeaker output |
| CN102802104A (en) * | 2012-08-16 | 2012-11-28 | 何永斌 | Moving-coil loudspeaker with area-alterable capacitive vibration sensor |
Also Published As
| Publication number | Publication date |
|---|---|
| EP2773132B1 (en) | 2017-05-24 |
| US20140241536A1 (en) | 2014-08-28 |
| CN104010263A (en) | 2014-08-27 |
| EP2773132A1 (en) | 2014-09-03 |
| US10219090B2 (en) | 2019-02-26 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104010263B (en) | Method and detector for diaphragm of loudspeaker offset | |
| CN104640051B (en) | Estimate the method for the vibrating diaphragm offset of loud speaker | |
| CN105704624B (en) | The method for controlling the diaphragm offset of dynamic loudspeaker | |
| CN104735600B (en) | Loudspeaker controller | |
| NL2014251B1 (en) | Echo cancellation methodology and assembly for electroacoustic communication apparatuses. | |
| CN105516874B (en) | Overheat protector for electrodynamic loudspeaker and protection method | |
| CN104349254B (en) | Controling shell installs the sound reproduction of loudspeaker | |
| CN105519133B (en) | Signal processing for MEMS capacitive energy converter | |
| US9258659B2 (en) | Method of detecting enclosure leakage of enclosure mounted loudspeakers | |
| US9154101B2 (en) | Active audio transducer protection | |
| EP2879401B1 (en) | Determining the temperature of a loudspeaker voice coil | |
| CN108668198A (en) | Apply the system and method for voice signal to the electronic acoustic transducer of multitone ring | |
| EP2387251B1 (en) | Sound reproduction and detection | |
| CN101933226A (en) | The signal conditioner that can suppress interference signal | |
| CN104113803A (en) | Multi-voice-coil based loudspeaker system | |
| CN108668206A (en) | Method for avoiding the vibrating diaphragm of electronic acoustic transducer from deviating | |
| JP6478910B2 (en) | Speaker control device | |
| US10389324B2 (en) | Audio reproduction device | |
| CN206364983U (en) | A kind of power amplifier and earphone system | |
| JP2003290162A5 (en) | ||
| WO2019191910A1 (en) | Speaker, terminal and speaker control method | |
| EP3375090A1 (en) | Device for amplifying an audio signal |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |